[1]College of Veterinary Medicine;
Yangzhou University;
Yangzhou 225009;
China;
[2]Jiangsu Agri-animal Husbandry Vocational College;
Taizhou 225300;
China;
[1]College of Veterinary Medicine;
Yangzhou University;
Yangzhou 225009;
China;
[2]Jiangsu Agri-animal Husbandry Vocational College;
Taizhou 225300;
China;
[1]College of Veterinary Medicine;
Yangzhou University;
Yangzhou 225009;
China;
[1]College of Veterinary Medicine;
Yangzhou University;
Yangzhou 225009;
China;
Class Ⅰ Newcastle disease virus; Nucleocapsid protein gene; Fluorescent quantitative RT-PCR;